Cargo trucks such as box trucks and semi-trailer trucks are the primary way of distributing and moving goods across land. The trucking industry provides an essential service to the American economy by transporting large quantities of raw materials, parts, and finished goods from manufacturing plants to wholesalers, distribution centers, and retail stores. Trucks are responsible for the majority of freight movement over land, and are vital components in the manufacturing, transportation, and warehousing industries.
In most cargo trucks, the floor of the cargo space is typically several feet above ground level. When loading or unloading goods using a hand truck or dolly, a ramp is often used to bridge the gap in elevation. However, for heavy or bulky loads, it is often a challenge to wheel the hand truck up and down the ramp in a safe manner. For example, due to the weight or bulk of the cargo, the hand truck may easy become out of control or gain speed down the ramp. Injury to the operator and damage to the cargo may result.